Step 1: Prepare the Pickle-Brined Coconut Milk (Optional, but Recommended). In a small bowl, combine the 1/8 cup of dill pickle brine with the 1/2 cup of coconut milk. Let sit while preparing other ingredients.

Step 2: Preheat Oven and Prepare Pans. Preheat the oven to 350°F (175°C). Butter three 8-inch round cake pans and line the bottoms with parchment paper, then butter the parchment. Dust with all-purpose flour and tap out the excess.

Step 3: Whisk Dry Ingredients. Whisk the all-purpose flour, cake flour, baking powder, dill pickle powder, and salt in a medium bowl. Set aside.

Step 4: Cream Butter and Sugar. Beat the butter and sugar in a large bowl with a mixer on medium speed until pale and fluffy, 3 to 5 minutes.

Step 5: Add Eggs and Extracts. Add the eggs and egg whites one at a time, beating well after each addition and scraping down the bowl as necessary. Beat in both extracts.

Step 6: Alternate Adding Dry Ingredients and Milk. Reduce the mixer speed to low and gradually beat in the flour mixture in three batches, alternating with the whole milk and the strained coconut milk/pickle brine mixture, starting and ending with the flour. Beat until just incorporated.

Step 7: Divide Batter and Bake. Divide the batter evenly among the prepared pans. Bake until the cakes are golden around the edges and a toothpick inserted into the centers comes out clean, 40 to 45 minutes.

Step 8: Cool Cakes. Transfer to racks and let the cakes cool in the pans for 15 minutes. Remove the cakes from the pans, remove the parchment, and return the cakes to the racks to cool completely.

Step 9: Make the Frosting – Combine Sugar and Egg Whites. While the cakes cool, make the frosting: Combine the sugar and egg whites in a heatproof bowl set over a pan of simmering water (do not let the bowl touch the water).

Step 10: Whisk Until Warm. Whisk until warm and the sugar is dissolved, 3 to 4 minutes.

Step 11: Beat into Meringue. Remove the bowl from the pan and beat with a mixer on medium speed until thick and glossy, 5 minutes. Increase the speed to medium-high and beat until stiff peaks form and the bottom of the bowl is cool, 7 more minutes.

Step 12: Add Butter Gradually. Reduce the speed to medium-low; Add the butter a few tablespoons at a time, beating well after each addition. (It’s OK if the frosting looks separated—just beat on medium-high speed until smooth again.)

Step 13: Add Extracts, Salt and Pickle Powder. Add both extracts, dill pickle powder, and the salt and continue beating until fluffy, 3 to 5 minutes.

Step 14: Assemble the Cake – Level Cakes (Optional). Trim the tops of the cakes with a long serrated knife to make them level, if necessary.

Step 15: Frost the Layers. Place 1 cake layer on a cake stand or platter. Spread with 1 cup frosting. Place the second layer on top and spread with another 1 cup frosting. Place the remaining cake layer on top and spread the remaining frosting over the top and sides of the cake.

Step 16: Coat with Coconut. Press the coconut into the sides of the cake. Garnish with finely chopped fresh dill (optional).